1. Field of the Invention
The present invention generally relates to an open/close mechanism for trays for stacking paper (paper trays) in image forming apparatuses. More particularly, the present invention relates to the open/close mechanism for paper trays that is arranged on a housing of an image forming apparatus.
2. Description of the Related Art
In a typical image forming apparatus, such as a printer, a copying machine, and a facsimile, in addition to feeding a paper to an image forming unit from an easily detachable paper cassette provided on the image forming apparatus, a paper can also be fed from an openable-and-closeable manual paper-feeding tray provided on a housing of the image forming apparatus. Image forming apparatuses of this type are disclosed in Japanese Patent No. 3728081 and Japanese Patent Application Laid-Open No. 2002-362786.
A conventional image forming apparatus disclosed in Japanese Patent No. 3728081 has a link member, one end of which is pivotably supported by a housing of the image forming apparatus while the other end of which is pivotably supported by the openable-and-closeable manual paper-feeding tray. The link member retains the manual paper-feeding tray at a predetermined angle.
In another conventional image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 2002-362786, a front cover is retained at a predetermined angle with a belt. In addition to the manual paper-feeding tray, the image forming apparatus includes a detachable paper feeding unit.
In recent years, how to downsize the image forming apparatuses has become a major issue. If a link or a belt is used for attaching the manual paper-feeding tray to the housing as in the conventional techniques, the size of the image forming apparatus increases by an amount corresponding to the link or the belt. Thus, it is difficult to downsize the image forming apparatus.
A typical paper feeding tray usually has a lock mechanism that restricts detachment or attachment of the paper feeding tray from the housing. Such lock mechanism requires space and therefore increases the size of the image forming apparatus.